The Mewtwo Deal

As you probably know, if you register both the Nintendo 3DS and Wii U versions of Super Smash Bros. 4 by March 31st, 2015, you get the Super Smash Bros. Melee veteran, Mewtwo. Nintendo eShop DLC codes will be distributed via email in "Spring" 2015 (the internet rumor says that it will be sent around May 2015). For you people that only have a 3DS (or 2DS) or only have a Wii U, and are planning to get only the Nintendo 3DS version or only the Wii U version of Super Smash Bros. 4, here is some strategies on how to get the Mewtwo fighter.

The easiest way, (and they way I did it) is if you only have the 3DS version and one of your friends only has the Wii U version, register both of the codes on YOUR Club Nintendo account, then when you get the DLC codes in Spring, keep the 3DS code, and tell them the Wii U code. If you only have the Wii U version and your friend only has the 3DS version, it doesn't matter. Register both the codes on your Club Nintendo account and tell them the 3DS code in Spring.
Another way, (this is hard), is search for a giveaway on the internet or a YouTube video for a Mewtwo DLC code, and sign up for the giveaway, and just hope for the best. But as we all know, you most likely won't win.
The final and Tough Nuggies way is to wait. Yep. You heard me (in your mind because I'm not talking to you and you're reading text). If you wait, you can buy a Mewtwo DLC code with real money. Nintendo has said that Mewtwo DLC MAY be available for purchase later (http://club2.nintendo.com/smash-promo/). The rumor is Winter 2015. But again, I'm sure you don't want to wait until WINTER NEXT YEAR, and if you do wait, your friends who got it in Spring are gonna rub it in your face. So, I would stick with the other two ways above if I were you. But even if you don't get Mewtwo...I'M GETTING SO TOUGH NUGGIES FOR YOU! (Just kiddin'! XD)